Molecular Engineering of a Conductive Metal–Organic Framework for Ultrasensitive, Rapid, Selective, and Reversible Sensing of Nitric Oxide

The selective, sensitive, low power, and portable detection of nitric oxide (NO) is important for environmental monitoring, industrial safety, and medical diagnostics. While tremendous progress has been made in detecting NO, existing technologies exhibit significant trade-offs in sensitivity, selectivity, portability, and power requirements for broad implementation. This paper presents the first synthesis of a novel class of two-dimensional conductive tetrapyrazinoporphyrazine-based metal-organic frameworks (MOFs) interconnected with Cu (DC-100 and DC-102) and Zn ions (DC-101) with unprecedented chemiresistive performance toward NO detection. DC-100 achieves an ultralow detection limit (0.47 parts-per-trillion (ppt)), rapid response (within seconds), high selectivity of NO over H2S, SO2, CO, NH3, and NO2, excellent reversibility, operation at room temperature, and low power requirements. The novel structural features and material-analyte interactions of DC-100 with NO represent a significant conceptual advance in molecular engineering of materials for NO detection, with potential applications in environmental monitoring, industrial safety, and medical diagnostics.